Oil well pump



A. G. GAGE oIL WELL PUMP May 9, 1933.

original' Filed May 14, 1926 l q 7 6 J 7 /fN E J/ n ,I1\ 1 We AII S n PI JH 2 1 f m a y y ;IIwino 1,.. 1 I 9N 1 1 1 11 IN1 1 1I11I1IIIII-I1mIl1 ...wl-Ilm! 2 I d@ z I /J//l/f//l/swwwm ,M W 7 -I.......TI JULI 1I 4%,.111., MMU .1 1 I/MW@ /IW @/f/Z/ II.. f Vf? l 6 M 9./ E Z W @n Alm A N I W\\ 0M n 9N Z -IVW INVENTOR. Qn 1* May'g, 1933.r

-A. G. GAGE OIL WELL PUIVLFl 2 sheets-sheet 2v Original Filed May 14 Y INVENTOR.

Patented May 9, 1933 omraosrii'res Pari-:Nr orifice ABJIIH'UIB G. GAGE, 0F LOS ANGELES, CALIFORNIA, ASSIGNQB TO ALTA VISTA HYDRALIC O0., LTD., OF LOS ANGELES, CALIFORNIA, A CORPORATION OI GALI- IOBNIA Y oiL WELL PUMP Application led 'lay 14, 1926, Serial No. 1094.098. Renewed October 7, 1982.

My present invention relates to hydraulically operated pumps to beused for raising water or yoil from deep bored wells, the objects being to provide a deep-well pump that is operatedby fluid pressure from the sur face of theground; also toI provide a simple single acting pump having few moving parte, and to provide a pump for `oil wells aving a' single acting pumping cylinder actuated by a double acting operating cyl- 1, hereinafter more fully described in de-l tail, to which is attached a depending cylinder 2. Within the cylinder 2 isa tubular plunger assembly comprising a piston head 3, a reduced diameter section 4 extending above the piston, and a second Section5, of

smaller diameter than section 4, extgnding below the piston head. By virtue of the dif- `ferential diameters of plunger sections 4 and 5, there is formed an annular pressure area on the upper end of piston 3 of comparatively smaller area than the downwardfacingpr'essure area on the lower end of vtlie piston. The advantages of providing such differential ressure areas at the ends of the piston section of the plunger will be made apparent in the description to follow. Plunger section 4'has a smooth sliding fit within a sleeve 6 attached to thelower end f s ofthe valve head and de ending therefrom within the piston cylin er 2, the vinterior of sleeve 6 forming a. displacement chamber for the well liquid being pumped. An outside sleeve 7 is placed eccentrically about the cylinder 2, the eccentric positioning of ,the

sleeve providing a longitudinal fluid passage 8 leading from theval've head to the bottom of cylinder 2.

A second cylinder 9 is seated in the lower part of the cylinder 2 and i's adaptedy to carry-slidably the plunger 5. The upper end of this cylinder forms thelower head for the driving cylinder 2.. Aport 10 connects the port 8 with the lower end of the cylinder 2 and a port 11 is formed by grooving the cylinder 6 andv connects an orifice 12 of the valve head with the top of the cylinder 2. The sleeve 7 is welded top and bottom to the cylinder 2, and at the to port 8 connects with the valve head y an orifice 13. In the bottom ofthe plunger 5 is a ball check valve 14.

Regarding the valve head 1, and with `reference to Figs. 2 and 4; the valve head the and bores were spread out on an elevated plane theyV wouldl appear as shown in Fi 2, and the relative position of the longitudinal bores and connecting ports are all shown' in Fig. 4,' the connecting ports being shown by dotted lines.

The bore 15 'carriesa main valve 16 liaving pistons 17 and 18 at its upper end and 19 and 20 at the lower end, the said pistons 18 and 19 being connected by a` waist 21. The bore 15 is closed at its upper and lower ends by plugs 22 and 23, respectivel havin fingers 22a and 23m which exten into en bores 17a and 20a, respectivel of the main valve, thus forming checks to eep thevalve from pounding. A bore 24 forms an inlet for the duid which operates the pump. A

bore 25 is the discharge means for the fluid Vwhich is used to operate the master valve. A

bore 26 is used as a discharge conduit through the valve head for the oil being discharged by the pump, and carries a dis charge valve 26a at the top end.

The central bore 27 carries a ilot valve 28 adapted to be operated by eac stroke of the piston and plungers, the upper end of bore 27 being closed y plug 27a. The inlet bore 24 is connected with the main valve bore 15 by a port 29 and with the pilot valve i the bore 25 by a bore 28 by a port 30. The master valve bore is connected with the pilot valve bore 27 by a port 31 bore32 and port 33 at the top, and by a port 34 bore 35 and port 36 at the bottom. 'Ihe main valve bore also carries a port 37 which discharges into the well, and a port 13 connecting into the port 8,

The pilot valve bore is connected with port 39 at its upper end and by a port 40 at the lower end. The inlet bore 24 is also connected withV the port 11 by a port 12. The pilot valve carries an upper piston 43, a lower plston 44 and a long stem 45 extending down into the plungers and piston below which are tubular, there being a lug 455 at the bottom and a second lug 45a near the top of the pilot valve stern adapted to be engaged by a bar 4a positioned within the top of the plunger 4. The ilot valve is caused to be moved a short distance at the end of each stroke of the plungers and piston by the engagement of bar 4a with lugs 45a and 456.

It is intended that the pump shall be screwed into the lower end of a string of tubing 46, and that there shall be a smaller string of tubing 47 within the tubing 46 adapted to conduct to the pump a high pressure operating Huid which preferably, though not necessarily, may be a clean fairly light oil. The Huid that is pumped by the device is conducted to the surface of the ground by the larger tubing 46. The operating Huid should be of a higher pressure than the pumped liquid.

The operation of thedevice is as follows: During the up stroke of the plunger 4, piston 3 and plunger 5, any oil filling the cylinder above the plunger 4 will be discharged through the valve 26a and conduit 46. During the downward movement of the plunger, oil' from the well is drawn in through the bottom valve 14, and through the tubular plungerk vinto the space above to be dischargedas before into the tubing 46. The upward movement of the plunger is obtained by admitting high pressure oil from the valve hea'd through the port 8 and port 10 into the bottom of the cylinder 2 below the piston 3; the downward movement of the plunger is obtained or accelerated by the constant pressure of oil, for example the high pressure operating Huid upon the small exposed area of the top of the piston, the oil under the piston being released by the valve head out into the well. This small volume l of Huid acting upon the smallerupper area of the piston, surges back and forth from the inlet bore 24, of the valve head through ports lland 12.

This present pump is designed to operate on a. small volume of high pressure oil entering under the piston 3 which is subseuently discharged into the well, and to raw in at each stroke from the well a end of the cylinder is the operating end and thev lower piston is ixed` to the plunger merely to set up a proper differential in area between the oil pumpedand the oil consumed in the operation of the pump. The area on the upper side of the piston 3 which is exposed to the high pressure operating oil should be only large enough to force the oil out from under the piston and through the valve head, and to afford a quick down ,movement of the plunger on the return stroke.

It will be recognized that although the differential of total applied force to raise the plunger has beenobtained in the present embodiment by a differential of oppositely facing areas exposed to the same fluid under the saine pressure, that the essence of the system resides not necessarily in a differential of areas, but in a differential of oppositely applied total effective forces, whether ornot these forces are caused by the same actuating Huid, or by actuating Huids at the same pressure.

In the operation of the valve head 1, hi h pressure operating oil is admitted into t e bore 24 from which it Hows to the pilot valve bore 27 by port 30. With the pilot valve in the position shown in Fig. 2, which position has been obtained by being pulled down due to the engagement of bar 4a with) lug 455 toward the-end of downward movement of the plungers, the operating. oil Hows from the pilot valve bore through ports 34, 35 and 36 into the bottom of the main valve, bore 16, forcing the main valve up to the top of its bore. With the main valve in this elevated position the operating oil then Hows from the inlet bore 24 through ports 29, 13, 8 and 10 into the bottom ofthe cylinder 2, forcing the plunger up. When the plunger reaches the top of its stroke'it moves the pilot valve upwardly, thus shutting off the owrof oil to 'the bottom-of Athe main valve bore, andv opening it, through ports 34, 35 and 36 and 40, to the discharge bore 25, andv at the same time allowin the operating oil to flow into the upper en l of the main valve bore through ports 31, 32 and 33, thus moving the main valve down to the bottom of its bore. lVith the main valve in this position, the high pressure operating oil is cut off from the cylinder 2, and the oil which entered under the piston then flows back out through ports 10, 8, 13 and 37 and into the and the main valve is again reversed.

The oil discharged from the main valve i bore, is discharged across the pilot valve bore and into the bore 25, and this bore 25 is connected into the tubing 46 in order that the static pressure of. the oil in that tubing shall in part balance the pressure of the high pressure operating oil on the valves, there being suilicient difference between the two pressures to operate the master Ivalve.

It will be noticed thatthe upper end of the plun er is exppsed to dirty well oil, and is su jected alternately to well pressure and column ressure, and that the lower end of the p unger is subjected always to dirty well oil under Well pressure. The clean high. ressure oil applied to the' upper end of t e piston head is then at a pressure higher than column pressure so that any lealrage taking place is leakage of clean oil traveling from the high pressure oil zone to the dirty oil end ofthe lun er at all times, thus continually washing t e plunger and maintaining it clean of sand particles., A part of the plunger above the lower end is subjected to clean oil under the alternating pressures of high pressure and well pressure, so that, whenever leakage takes place at that zone, clean oil is traveling down toward the dirty Well oil zone at the lower end of the plunger, and thus also cleaning the plunger at its lower end. 1

It is to be understood that I do not limit myself to the exact arrangement of the valves and ports in the valve head and that many changes might be made .in the invention as shown without departing from the v spirit thereof, as claimed.

Having .thus described my invention,-I claim:

1. In an oil well pump in combination, a cylinder, a tubular piston forthe cylinder, a tubular plunger part extending from one end of the piston and adapted to decrease the area of the piston to provide an area of smallextent against which a high pressure fluid may operate to move the iston and plunger through a filling stro e of `the pump, a cylinder for the plunger, a discharge valve for the plunger cylinder, a port adapted to conduct a high pressure fluid constantly against the small ex osed area of the piston, a second hollowed p unger part extending from the other end of the piston and adapted to decrease the area thereof to a determined extent less than the area of the first mentioned plunger, a cylinder for the second plunger, an inlet valve for controlling flow of operating fluid to the piston-and plungers, a valve head for vthe pump, a port connecting with the valve head and adapted to conduct the high pressure operating fluid to and from the larger exposed area of the piston, and valves mounted in the valve head for alternately admitting into and discharging the operatingfluid from said second namedport whereby the area of the piston to provide an area of relatively small extent against which aV high pressure AHuid may operate to move the piston and plunger through a filling stroke of the pump, a cylinder for the plunger, a displunger cylinder, y

charge valve for the means for admitting a high pressure duid constantly against the small exposed area of the piston, a second tubular vplunger part extendingfrom the other end of the piston and adapted to decrease the area thereof to a determined extent less than the area of the first mentioned plunger, a cyl-` inder for the second plunger part, an inlet valve for the pump mounted in said tubular piston and plungers, and a valve head for the pump adapted to conduct a high pressure operating fluid against and away from the larger exposed area of the piston whereby the piston andl plungers may through a discharging stroke.

3; In combination, in an oil Well pump, a cylinder, a tubularpiston for the cylinder, a tubular plunger part extending trom one end of the piston and adapted to decrease the area of the piston to provide an area of relatively small extent against which a high pressure fluid may operate to move the piston and plunger part through a filling stroke of the pumA ,a cylinder for the plungi er, a dschar e va ve for the plunger cylinder, means or admitting a high pressure fluid constantly against the small exposed area of the piston, a second tubular plunger part extending from the other end of the cylinder for the second plunger, an inlet valve' for the pump mounted in said tubular piston and plungers, and means for conducting a high pressure operating fluid to and from the larger exposed .area of the piston whereby the piston and plungers may be operated through a. discharging' stroke of the pump.

4. In a pump of the kind described, the combination of a pump barrel having a bore of relatively small diameter above and a relatively large bore below, a valve-head at the upper end of the barrel, a plunger having a tubular body with its upper portion mounted to reciprocate in the said small bore of the barrel below the valve-head, said plunger having a medial piston-head mounted to reciprocate in the bore of larger diameter, the tubular body ofv said plunger above the piston-head being of larger diameter than beI operated I' plunger having a head whereby in the tubular body of the plunger, means for admitting fluid under high pressure to the barrel below the said piston-head to raise the plunger, means for admitting fluid under pressure to the interior of the barrel above the piston-head and below the bore of reduced diameter, and a valve in the valve-head operating to lpass the pumped fluid upwardly through the valve-head on each up-stroke of the plunger, a pipe confining a well liquid discharge column above said valve head, and a second pipe confining a high pressure fluid column above the valve head, one of said pipes being within the other.

5. In a pump of the kind described, the combination of a pump barrel having a bore of relatively small diameter above and a relatively large bore below, a valve-head at the upper end of the barrel, a plunger having a tubular body with its upper portion mounted to reciprocate in the said small bore of the barrel below the valve-head, said medial piston head mounted to reciprocate in the bore of larger diameter, the tubular body of said plunger above the piston-head being of larger diameter than the body of the plunger below the piston-head whereby an effective annular area is formed on the under side of the pistonliead of greater area than the annular area on the upper side of the piston head, a checkvalve in the tubular body of the plunger, means forperiodically admitting fluid under higher pressure than the pressure in the pumped column of liquid to the barrel below the said piston-head to raisethe plunger, means for constantly admitting fluid under pressure to the interior of the barrel above the piston head and below the bore ot reduced diameter, to actuate the plunger in its down-stroke, and a valve in the valvehead operating to pass'the pumped liquid upwardly through the valve-head on each up-stroke of the plunger.

6. In a pump of the kind described, the combination of a pump barrel having a bore of relatively small diameter above and a relatively large bore below, a valve-head at the upper end -of the barrel, a plunger having a tubular body with its upper portion mounted to reciprocate in the said small.

bore of the barrel below the valve-head, said plunger having a medial piston-head to reciprocate in the bore of larger diameter, the tubular body oi said plunger above the piston-head being of larger diameter 'than Athe body of the plunger below the piston-head whereby an effective annular area is formed on the under side of the piston-head of greater area than the annular area on the upper side of the iston-head, there being a fluid passage extending through said valve head and barrel tothe upper side of the piston, a check-valve in the tubular body o the plunger, a fluid-actuated valve for admitting fluid under high pressure to the interior of the barrel below the pistonhead to raise lthe plunger, and for opening communication from the interior of the barrel below the piston-head to the exterior, to permit. exhaust of the fluid under pressure on the down-stroke of the plunger, actuated valve also operating to control the application offhigh pressure fluid to the upper face of .the piston, and an automatic valve for controlling the flow of the yoperating fluid'to the fluid-operated valve.

7. In a well pump of the character described, the combinations comprising a well pipe, a pump barrel suspended within the well on said pipe, a fluid pressure actuated plunger within said barrel, means for maintaining a relatively small effective fluid pressure force constantly on the plunger to press it in. one direction of its movement, and means for intermittently applying a relatively'larger opposing fluid pressure force on the plunger to lnove it in the other direction.

48. In a well pump of the character described, the combination comprising a well pipe, a pump barrel suspended within the well on said pipe, a fluid pressure. actuated plunger within said barrel, a pressure area on said plunger facing in one direction, means for constantly maintaining a fluid under pressure on said pressure area to press the plunger in one direction of its movement, a second pressure area on said plunger facing in the opposite direction to the first said area, and means for intermittently applying fluid under pressure to the said last mentioned pressure area, the total eective pressure applied to said last mentioned area being greater than the total effective pressure on said oppositely facingk first mentioned area.

9. In a well pump of the character described, the combination comprising a well pipe, a pumpybarrel suspended within the well on said pipe, a fluid pressure actuated plunger within said barrel, a pressure area on said plunger facing in one direction, means for constantly maintaining la fluid under pressure on said pressure area, a relatively larger pressure area on said lunger facing in the opposite direction, an means for intermittently applying a fluid under pressure to the last mentioned pressure area, whereby the plunger is alternately raised and lowered.

10. In a pump of the character described, the combination of a pump barrel, a plunger mounted to be reciprocated therein, a pressaid fluid surel area on said plunger facing in one div for constantly maintaining an eiective duid ressure downwardly on the plunger for downward movement thereof` and means for intermittently a plyin an eifective duid pressure upward y on t e plunger suliicient 'to overb'alance the weight of the. plunger plus the effective downwardly acting fluid pressure, whereby the plunger is alternately raised and lowered,

12. Ina pump of the character described,

the combinationof a pump barrel, a plunger mounted to be reciprocated therein, an upwardly facing effective area on said plun er,

means for constantly maintaining an e ective Huid pressure on said upwardly facing area whereby said plunger is constantly pressed downward, a downwardly vfacing effective area on said plunger, and means for intermittently applying an effective fluid pressure on said downwardly facing area whereby said plunger is intermittently pressed upward, the total eifective pressure on saiddownwardly facing area being greater than the total effective pressure on said upwardly facing area.

13.- In a pump of the character-described, the combination of a pump barrel, a plunger mounted to be reciprocated therein, an upwardly facing effective area on said plunger,

means for constantly maintaining a fluid under pressure on said upwardly facing area whereby said plunger 1s constantly pressed downward.,l a downwardly facing elective areaon said plunger, saiddownwardly fac- :ing elfective area being relatively larger than said upwardly facing effective area, and means for intermittently applying the same fluid under pressure on. said downward- 1y facing area, whereby the said plunger is alternately raised and lowered. l 14. In a. pump-'of the character the combination of a pump barrel having a vmedial bore, an upper bore of reduced diameter, above said medial bore, and a lower bore of still further reduced diameter below said medial bore, a hollow plunger mounted to reciprocate in the pump barrel, said hollow plunger comprising a piston head adapted Yto work in the said medial bore of the barrel, an upper plunger part of reduced diameter extending upwardly from said pistou-head and adapted to work in the said reduced upper bore, whereby an updescribed,

wardly facing annular area is provided on the upper end of the said iston-head, a lower plunger part of reduce diameter extendin downwardly from said piston-head and a aptedl to work in the saidy reduced 'loA lower bore, whereby a downwardly facing L annular area is of the iston-hea upwar l facing annular area on the uppcu:v end of t e piston-head, means for constantadmitting fluid under pressure to the meprovided on the lower en l dial bore of the barrel above the piston-head,

and valvular 'means for interm1ttently admitting fluid under pressure to the medial bore of the barrel below the piston-head.

. l5. In a pumpofftlie character described, the combination of a pump barrel having a medial bore, an upper bore of reduced diameter above said medial bore, and a lower bore of still further reduced diameter below' said medial bore, a valve headat the upper end of the barrel, a hollow plunger mounted to reciprocate in the pump barrel, said hollow plunger comprising a piston head adapted to work in the said medial bore of of Vgreater extent than the the barrel, an upper plunger part of reduced diameter extending upwardly from said piston-head and adapted to work in the said reduced upper bore, whereby an upwardly facing annular area is rovided on the upper end of the said plston-head, a lower plunger part of reduced diameter extending downwardly from said piston-head and y adapted to. work in the said reduced lower bore, whereby a downwardly facing annular area is provided on the lower'end of the piston-head of greater extent than the upwardl facing annular area on the up er end of the piston-head, a shell surroundlng the pump barrel with clearance, and bein connected to the valve head at its upper end and connected to the barrel below the medial bore thereof at its lower end, there being a conduit in the valve head for admission to the pump of high-pressure operating liuid,

said conduit being communicable with the medial bore of the barrel above the pistonhead, and valvular mechanism in the piston head for intermittently admitting high ressure fluid from thesaid conduit to the c earance space between the pump barrel and sur rounding shell, there being a port in the wall of the barrel at the lower end of its medial bore providing communication between the said clearance space and the medial bore below the piston-head for the passageof high pressure liuid.

16. In a pump of the character described, the combination of a pump barrel having a medial bore, an upper bore of reduced diameter above said medial bore, and a lower bore of still further reduced diameter below said medialy bore, a hollow plunger mounted to reciprocate in the pump barrel, said hollow plunger comprising a piston head ada ted to work in the said medial bore of t e barrel, an upper plunger part of reduced diameter extending upwardl from said piston-head and adapted to wor in the said' reduced upper bore, whereby an upwardly facing annular area is provided on the upper end of the said piston-head, a

lower plunger part of reduced diameter extendin downwardly from said piston-head and a apted towork in the said, reduced lower bore, whereby a downwardly facing annular area is provided on the lower end of the iston-head of greater extent than the upwar y facing annular area on the upper end o f the piston-head, 'means for admittin clean high-pressure oil to the barrel an to a medial portion of the plunger above the upwardly facing annular area thereof, the .said clean high-pressure oil acting to press the lunger downward and to maintain the p unger clean by virtue of leakage,

means for intermittently admitting clean high-pressure oil to the barrel and to a medial ortion of the plunger below the downwar y facing annular area thereof, the said clean igh-pressure oil acting intermittently to press the plunger upward and to maintain the plunger clean by virtue of leakage.

17. In 'a pump of the character described, the combination of a pump barrel, a plunger mounted to be reciprocated therein, an upwardly facing effective area on said plunger and intermediate the ends thereof, a downwardly facin effective area on said plunger and interme iate the ends thereof, means for constantly admitting clean high-pressure oil to the barrel and to a medial portion of the plunger above the said upwardly facing area, said clean high-pressure oil acting to exert pressure downward on the plunger and to maintain the plunger clean A by virtue of leakage, means for intermittently admitting clean high-pressure oil to the barrel and to a medial portion of the plunger below the said downwardly facing area, the total pressure of the high-pressure oil against the said downwardly facing area befluid pressure upward on the said plunger` for upward movement thereof, means for constantly malntaimng an effective pressure of clean oil downward on said plunger, the

last mentioned effective downward pressure being less than the first mentioned effective upward pressure, whereby the plunger is .cations of iluid pressure, said c pressed downward between upward applican oil belng applied to a medial portion of the plunger whereby the said plunger is maintained clean by virtue of leakage.

19. In a pump of the character described, the combination comprising a pump barrel, a iuid pressure actuated plunger within said barrel, means for applying a relatively small effective fluid pressure force on the plunger to press it in one direction of its movement, means for applying a relatively larger luid pressure force on the plunger to move it in an opposite direction, the first mentioned means comprising means for applying clean oil to a medial portion of the plunger whereby said plunger is maintained clean by virtue of leakage.

20. In a pump of the character described, the combination comprising a pump barrel, a fluid pressure actuated plunger within said barrel, a pressure area on said plunger facing in one direction, a relatively larger pressure area on said plunger facing in the opposite direction, and means for applying fluid pressure to saidareas to operate the plunger, said means comprising means for applying clean oil to a medial portion of the plunger whereby said plunger is maintained clean b virtue of Huid leakage.

21. In a wel pump of the character described, the combination of a pump barrel having a medial bore, an upper bore of reduced diameter above said medial bore, and a lower bore of still further reduced diameter below said medial bore, a hollow plunger -mounted to reciprocate inthe pump barrel,

said hollow plunger comprising a piston head adapted to work in said medial bore of the barrel, an upper plunger part of reduced diameter extending upwardly from said pistonhead and adapted to work in the said reduced upper bore, whereby an upwardly facing annular area is provided on the upper end of the said piston-head, a lower plunger part of reduced diameter e'xtending downwardly from said piston-head and adapted-to work in the said reduced lower bore, whereby a downwardly facing annular area is provided on the lower en of the piston-head of greater extent than the upwardly facing annular area on the upper end of the piston-head, means for admitting fluid under pressure to the medial bore of the barrel above the piston-head, valvular means above said pump barrel and operable to intermittently admit fluid under -pressure to the medial bore of the barrel below the piston-head.

22. In a pump, a hollow plunger carrying an operating piston and a pumping piston, means conining a hydraulic column in communication with the upper side of the operating piston, means includin a tube surrounding the plunger and the said means,

confining a hydraulic column and convefying pressure therefrom to the lower side o the operating piston, means conning a third hydraulic column, mea-ns automatically operated by movement of the plunger to intermittently superimpose the third column on the last mentioned column, and a pump barrel containing the umping piston.

23. In a pump, a we l casing and a pump mechanism suspended from the casing and insertable through the casing and withdrawable therefrom, the pump mechanism comprising the followi a head suspended fromV the casing, a well tubing coaxiall connected to and pendent from the hea concentric pump barrels within the tubing, a `pump plunger having an operating piston and a pumping iston, the operating piston Working in the ar er barrel, the pumping iston working in t e smaller barrel, means lncludinr the tubin and the larger barrel for confining two ydraulic columns, one communicating pressure to the lower side of the operating piston and the other to the upper side thereof, means confining a third hydraulic column, and means for superimposing the third column on the other two columns including means for intermittently applyingthe third column to at least one o the other two columns.

24. In a well pump, a plunger, a vtube to contain a hydraulic column, the said column o rating against a portion of the lower side o the plunger, a tube to contain a hydraulic column, the said column operating a p unger and a conduit to contain the column of fluid to be lifted by the plunger, the latter column being sustained by the remainder of the upper surface of the plunger, the first portion havin a lar er area than the second portion, an the sai plunger operating in one of the tubes.

25. -In a well pump, a plunger, a tube to contain a hydraulic column the said column operatin against anannulus on the lower side of t e plunger, a tube-to contain a hydraulic column, the said column o rating against an annulus on the upper si e of the plunger, and a conduit to contain the column of fluid to be lifted by the plunger, the latter column being sustained by the remainder of the up r surface of the plunger, the first annu us havin a larger area. than the second annulus, an the said plunger operating in one of the tubes.

In testimony whereof, I have hereunto signed my name to this specification.

ARTHUR G. GAGE.

gainst a portion of the upper side of the i 

